1. Field of the Invention
The present invention relates to an intraocular lens that may accommodate automatically, and more particularly to an intraocular lens that may accommodate automatically, wherein the position of the central optic of the intraocular lens in the eyeball may be adjusted so as to change the entire refractive power of the eyeball.
2. Description of the Related Art
Usually, an intraocular lens may be used to replace the original crystalline lens when being aged or diseased. The intraocular lens may be mounted into the capsular bag of the patient. If the capsular bag is not complete, the intraocular lens may be mounted in the ciliary sulcus of the patient. However, the intraocular lens of prior art has a constant focus, so that it cannot accommodate automatically.
A conventional intraocular lens 100 in accordance with the prior art shown in FIG. 1 comprises a central optic 101, and two haptics 102 connect with the central optic 101.
As shown in FIG. 2, the conventional intraocular lens 100 is mounted in the capsular bag 200. However, the anterior chamber distance (ACD) is fixed, and the refractive power thereof cannot be adjusted.
As shown in FIG. 3, the conventional intraocular lens 100 is mounted in the ciliary sulcus 300 when the capsular bag 200 is not complete. The two haptics 102 of the conventional intraocular lens 100 are settled on the ciliary sulcus 300. However, the anterior chamber distance (ACD) is fixed, and the refractive power thereof cannot be adjusted.
There are many ways to achieve the accommodating need of human eye after cataract extraction. The first is implantation of multifocal lens, which provide many different focal areas in a lens it self. The U.S. Pat. Nos. 4,666,446, 4,710,193, 4,759,762, 5,225,858, 5,326,348, 5,507,806 are of category of multifocal design. This category of multifocal design is a compromised way of accommodation, they are not voluntary and different areas of blurred image hamper the visual field and the light amount is decreased.
The second is using a small aperture to increase the depth of field. Which is disclosed by U.S. Pat. No. 4,759,762. This method is compromised by the decreased light transmission amount and loss of visual field.
The third method is a group of designs of intraocular lens, which are directly driven or indirectly activated by the contraction of ciliary muscle. The U.S. Pat. Nos. 4,842,601, 4,888,012, 4,892,543, 4,932,966, 4,944,082, 5,476,514, 5,578,081, 5,607,472, 5,843,188, 6,197,059 B1 are of this category. This category of designs have many problems which still under investigation. The most doubtful problem is the effectiveness and the stability of the mechanical attachment of lens with the ciliary muscle.
The others, as in U.S. Pat. No. 6,200,342 B1 is an Intraocular lens which change power by pupil contraction. The U.S. Pat. Nos. 5,108,429, 5,171,266, 5,203,788, 5,800,533 are a series of intraocular lens designs, which can fine adjusting the power by micro motor or by electromagnetic means. These designs are not for accommodating needs of human eye and the mechanical arrangement are quite different with the present invention. The present invention is an intraocular lens, which can change the position along the visual axis by will and still eliminate the need of interaction with ciliary muscle. The fixation of this invention into human eye is quite the same with the tremendous successfully used classical fixed focal intraocular lenses. So the present invention has many advantages compared with the prior art of this field.
The present invention is to provide an intraocular lens wherein the position of the central optic at the visual axis may be changed by control of the user.
The primary objective of the present invention is to provide an intraocular lens that may accommodate automatically, including a central optic having an anterior optic connected with the stroke cylinder, a posterior optic connected with the outer core which is connected with the stroke cylinder, thereby enclosing the central optic in an inner periphery. The central optic is connected with the outer core by at least one spring haptic, thereby forming the intraocular lens that may be placed in the capsular bag of an eyeball. When the capsular bag of the eyeball is not complete, the two haptics connecting the outer core can fix in the ciliary sulcus of the eyeball, so that the intraocular lens may be positioned.
Accordingly, the position of the central optic of the intraocular lens in the eyeball may be adjusted so as to change the entire optical power of the eyeball. Thus, when the patient implanted with the intraocular lens of the present invention to have a far seeing, the central optic is located at the optimal position to have a far seeing. When the patient implanted with the intraocular lens of the present invention to look at the ground, the central optic of the intraocular lens may linearly displace forward through a determined distance automatically. When the patient implanted with the intraocular lens of the present invention to read a predetermined nearest distance, the central optic of the intraocular lens may be adjusted automatically to be located at the front stop position close to the anterior optic.
The power source of the intraocular lens of the present invention is the gravity. Thus, by change of the inclined angle of the user, or by variation of the external magnetic field, the push force that is exerted on the central optic of the intraocular lens may be regulated, so as to actively control the position of the central optic of the intraocular lens, so that the user may actively control and regulate the refractive power of the eyeball.
In accordance with one aspect of the present invention, there is provided an intraocular lens that may accommodate automatically, comprising: a central optic, an outer core, a stroke cylinder, an anterior optic, a posterior optic, at least one spring haptic, and a magnetic heavy part, wherein, the anterior optic at a front end of the central optic is connected with the stroke cylinder, the posterior optic at a rear end of the central optic is connected with the outer core, the outer core is connected with the stroke cylinder, thereby enclosing the central optic in an inner periphery, the central optic is connected with the outer core by at least one spring haptic, the intraocular lens may be placed in the capsular bag of an eyeball, a power source of the intraocular lens is the gravity, by change of an inclined angle of a user, a push force that is exerted on the central optic of the intraocular lens may be regulated, so as to actively control a position of the central optic, so that the user may actively control and regulate the refractive power of the eyeball.
Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings.